Billy,
do you remember about 20 years ago or so that sunken boat that was straight across from Havasu Landing on the back side of the island? Big wood cruiser with twin SBCs, twin v-drives and so on. I think it was there 2 summers before someone drug it up. If I remember right it had Vette valve covers on both motors, so maybe they were old 283s or 327s. I wasn't smart (sober) enough at the time to try to salvage anything off it!